Dynamics of sediment carbon stocks across intertidal wetland habitats of Moreton Bay, Australia

AbstractThere is growing interest in carbon stocks and flows in seagrass ecosystems, but recent global reviews suggest a paucity of studies from Africa. This paper reviews work on seagrass productivity, biomass and sediment carbon in Africa. Most work was conducted in East Africa with a major geographical gap in West Africa. The mean above-ground, below-ground and total biomasses from all studies were 174.4, 474.6 and 514 g DW m

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Blue carbon stocks and exchanges along the California coast

Biogeosciences ◽

10.5194/bg-18-4717-2021 ◽

2021 ◽

Vol 18 (16) ◽

pp. 4717-4732

Author(s):

Melissa A. Ward ◽

Tessa M. Hill ◽

Chelsey Souza ◽

Tessa Filipczyk ◽

Aurora M. Ricart ◽

...

Keyword(s):

Salt Marsh ◽

Salt Marshes ◽

Carbon Sources ◽

Carbon Stocks ◽

Blue Carbon ◽

California Coast ◽

Seagrass Meadows ◽

Terrestrial Habitats ◽

Isotope Mixing Models ◽

Sediment Carbon

Abstract. Salt marshes and seagrass meadows can sequester and store high quantities of organic carbon (OC) in their sediments relative to other marine and terrestrial habitats. Assessing carbon stocks, carbon sources, and the transfer of carbon between habitats within coastal seascapes are each integral in identifying the role of blue carbon habitats in coastal carbon cycling. Here, we quantified carbon stocks, sources, and exchanges in seagrass meadows, salt marshes, and unvegetated sediments in six bays along the California coast. In the top 20 cm of sediment, the salt marshes contained approximately twice as much OC as seagrass meadows did, 4.92 ± 0.36 kg OC m−2 compared to 2.20 ± 0.24 kg OC m−2, respectively. Both salt marsh and seagrass sediment carbon stocks were higher than previous estimates from this region but lower than global and US-wide averages, respectively. Seagrass-derived carbon was deposited annually into adjacent marshes during fall seagrass senescence. However, isotope mixing models estimate that negligible amounts of this seagrass material were ultimately buried in underlying sediment. Rather, the vast majority of OC in sediment across sites was likely derived from planktonic/benthic diatoms and/or C3 salt marsh plants.

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Blue Carbon Stocks and Exchanges Along the Pacific West Coast

10.5194/bg-2021-27 ◽

2021 ◽

Author(s):

Melissa A. Ward ◽

Tessa M. Hill ◽

Chelsey Souza ◽

Tessa Filipczyk ◽

Aurora M. Ricart ◽

...

Keyword(s):

Salt Marsh ◽

Salt Marshes ◽

Carbon Sources ◽

Carbon Stocks ◽

Blue Carbon ◽

Seagrass Meadows ◽

The Pacific ◽

Terrestrial Habitats ◽

Isotope Mixing Models ◽

Sediment Carbon

Abstract. Salt marshes and seagrass meadows can sequester and store high quantities of organic carbon (OC) in their sediments relative to other marine and terrestrial habitats. Assessing carbon stocks, carbon sources, and the transfer of carbon between habitats within coastal seascapes are each integral in identifying the role of blue carbon habitats in coastal carbon cycling. Here, we quantified carbon stocks, sources, and exchanges in seagrass meadows, salt marshes, and unvegetated sediments in six bays along the Pacific coast of California. The salt marshes studied here contained approximately twice as much OC as did seagrass meadows, 23.51 ± 1.77 kg OC m−3 compared to 11.01 ± 1.18 kg OC m−3, respectively. Both seagrass and salt marsh sediment carbon stocks were higher than previous estimates from this region but lower than global and U.S.-wide averages, respectively. Seagrass-derived carbon was deposited annually into adjacent marshes during fall seagrass senescence. However, isotope mixing models estimate that negligible amounts of this seagrass material were ultimately buried in underlying sediment. Rather, the vast majority of OC in sediment across sites was likely derived from planktonic/benthic diatoms and C3 salt marsh plants.

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Organic carbon inventories in natural and restored Ecuadorian mangrove forests

10.7287/peerj.preprints.71 ◽

2013 ◽

Author(s):

Amanda G DelVecchia ◽

John F Bruno ◽

Larry K Benninger ◽

Marc Alperin ◽

Ovik Banerjee ◽

...

Keyword(s):

Organic Carbon ◽

Carbon Content ◽

Carbon Storage ◽

Organic Matter Content ◽

Carbon Stocks ◽

Organic Carbon Content ◽

Mangrove Forests ◽

Storage Potential ◽

Sediment Carbon

Because mangroves can capture and store organic carbon, their protection and restoration is an obvious component of climate change mitigation. However, there are few empirical measurements of long-term carbon storage in mangroves or of how storage varies across environmental gradients. The context dependency of this process combined with geographically limited field sampling has made it difficult to generalize regional and global rates of mangrove carbon sequestration. This has in turn hampered the inclusion of sequestration by mangroves in carbon cycle models and in carbon offset markets. The purpose of this study was to estimate the relative carbon capture and storage potential in natural and restored mangrove forests. We measured depth profiles of soil organic carbon content in 72 cores collected from six sites (three natural, two restored, and one afforested) surrounding Muisne, Ecuador. Samples up to 1 m deep were analyzed for organic matter content using loss-on-ignition and values were converted to organic carbon content using an accepted ratio of 1.72 (g/g). Results suggest that average soil carbon storage is 0.055 ± 0.002 g∙cm-3 (11.3 ± 0.8% carbon content by dry mass, mean ± 1 SE) up to 1 m deep in natural sites, and 0.058 ± 0.002 g∙cm-3 (8.0 ± 0.3%) in restored sites. These estimates are concordant with published global averages. Evidence of equivalent carbon stocks in restored and afforested mangrove patches emphasizes the carbon sink potential for reestablished mangrove systems. We found no relationship between sediment carbon storage and aboveground biomass, forest structure, or within-patch location. Our results demonstrate the long-term carbon storage potential of natural mangroves, high effectiveness of mangrove restoration and afforestation, a lack of predictability in carbon storage strictly based on aboveground parameters, and the need to establish standardized protocol for quantifying mangrove sediment carbon stocks.

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Mangrove sediment carbon stocks along an elevation gradient: Influence of the late Holocene marine regression (New Caledonia)

Marine Geology ◽

10.1016/j.margeo.2018.07.005 ◽

2018 ◽

Vol 404 ◽

pp. 60-70 ◽

Cited By ~ 5

Author(s):

Adrien Jacotot ◽

Cyril Marchand ◽

Brad E. Rosenheim ◽

Eugene W. Domack ◽

Michel Allenbach

Keyword(s):

Late Holocene ◽

New Caledonia ◽

Elevation Gradient ◽

Carbon Stocks ◽

Mangrove Sediment ◽

Sediment Carbon

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Organic carbon inventories in natural and restored Ecuadorian mangrove forests

10.7287/peerj.preprints.71v1 ◽

2013 ◽

Author(s):

Amanda G DelVecchia ◽

John F Bruno ◽

Larry K Benninger ◽

Marc Alperin ◽

Ovik Banerjee ◽

...

Keyword(s):

Organic Carbon ◽

Carbon Content ◽

Carbon Storage ◽

Organic Matter Content ◽

Carbon Stocks ◽

Organic Carbon Content ◽

Mangrove Forests ◽

Storage Potential ◽

Sediment Carbon

Because mangroves can capture and store organic carbon, their protection and restoration is an obvious component of climate change mitigation. However, there are few empirical measurements of long-term carbon storage in mangroves or of how storage varies across environmental gradients. The context dependency of this process combined with geographically limited field sampling has made it difficult to generalize regional and global rates of mangrove carbon sequestration. This has in turn hampered the inclusion of sequestration by mangroves in carbon cycle models and in carbon offset markets. The purpose of this study was to estimate the relative carbon capture and storage potential in natural and restored mangrove forests. We measured depth profiles of soil organic carbon content in 72 cores collected from six sites (three natural, two restored, and one afforested) surrounding Muisne, Ecuador. Samples up to 1 m deep were analyzed for organic matter content using loss-on-ignition and values were converted to organic carbon content using an accepted ratio of 1.72 (g/g). Results suggest that average soil carbon storage is 0.055 ± 0.002 g∙cm-3 (11.3 ± 0.8% carbon content by dry mass, mean ± 1 SE) up to 1 m deep in natural sites, and 0.058 ± 0.002 g∙cm-3 (8.0 ± 0.3%) in restored sites. These estimates are concordant with published global averages. Evidence of equivalent carbon stocks in restored and afforested mangrove patches emphasizes the carbon sink potential for reestablished mangrove systems. We found no relationship between sediment carbon storage and aboveground biomass, forest structure, or within-patch location. Our results demonstrate the long-term carbon storage potential of natural mangroves, high effectiveness of mangrove restoration and afforestation, a lack of predictability in carbon storage strictly based on aboveground parameters, and the need to establish standardized protocol for quantifying mangrove sediment carbon stocks.

Download Full-text